T3651.hs:11:11:
    Couldn't match type ‘Bool’ with ‘()’
    Inaccessible code in
      a pattern with constructor: U :: Z (), in an equation for ‘unsafe1’
    In the pattern: U
    In an equation for ‘unsafe1’: unsafe1 B U = ()

T3651.hs:14:11:
    Couldn't match type ‘Bool’ with ‘()’
    Inaccessible code in
      a pattern with constructor: U :: Z (), in an equation for ‘unsafe2’
    In the pattern: U
    In an equation for ‘unsafe2’: unsafe2 B U = ()

T3651.hs:17:11:
    Couldn't match type ‘Bool’ with ‘()’
    Inaccessible code in
      a pattern with constructor: U :: Z (), in an equation for ‘unsafe3’
    In the pattern: U
    In an equation for ‘unsafe3’: unsafe3 B U = True